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A diborane based on the 1,8-biphenylenediyl backbone displays a high affinity for hydrazine while also behaving as a cyanide sponge., As part of our interest in the chemistry of polydentate Lewis acids as hosts for diatomic molecules, we have investigated the synthesis and coordination chemistry of bidentate boranes that feature a large boron–boron separation. In this paper, we describe the synthesis of a new example of such a diborane, namely 1,8-bis(dimesitylboryl)triptycene (2) and compare its properties to those of the recently reported 1,8-bis(dimesitylboryl)biphenylene (1). These comparative studies reveal that these two diboranes feature some important differences. As indicated by cyclic voltammetry, 1 is more electron deficient than 2; it also adopts a more compact and rigid structure with a boron–boron separation (4.566(5) Å) shorter by ∼1 Å than that in 2 (5.559(4) Å). These differences appear to dictate the coordination behaviour of these two compounds. While 2 remains inert toward hydrazine, we observed that 1 forms a very stable μ(1,2) hydrazine complex which can also be obtained by phase transfer upon layering a solution of 1 with a dilute aqueous hydrazine solution. The stability of this complex is further reflected by its lack of reaction with benzaldehyde at room temperature. We have also investigated the behaviour of 1 and 2 toward anions. In MeOH/CHCl3 (1/1 vol) both compounds selectively bind cyanide to form the corresponding μ(1,2) chelate complexes with a B–C 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 1111111111111111111111111111111111 1111111111111111111111111111111111 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 1111111111111111111111111111111111 1111111111111111111111111111111111 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 1111111111111111111111111111111111 1111111111111111111111111111111111 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 N–B bridge at their cores. Competition experiments in protic media show that the anionic cyanide complex formed by 1 is the most stable, with no evidence of decomplexation even in the presence of (C6F5)3B.

To achieve the surface plasmon resonance (SPR) mode splitting in infrared wavelength band, and to improve the figure-of-merit (FOM) of grating based SPR sensor, in this article we present a new composite grating structure, which consists of double metal gratings, and study the gas sensing performance. Split modes of SPR in composite metal grating are observed by using the finite difference time domain method. The original structure symmetry is broken and changed with increasing relative displacement between the double gratings, as a result, the resonant modes move to opposite directions. Calculated electric field distribution of the two separate resonant modes displays two different degrees of coupling effect between the double gratings. When the relative displacement is further increased till the double gratings are connected to form a new symmetrical single grating, the separate resonant modes will merge into another single resonant mode. If the refractive index of analyte (na) is in a range 1.01≤na≤1.05 and the relative displacement of double gratings is zero, the wavelength sensitivity based on composite metal grating gas sensor reaches 1207.5 nm/RIU (per refractive index of unit) and the FOM is obtained to be 1290.7, while the relative displacement of the double gratings is 100 nm, for the double split modes the wavelength sensitivities are 1205.0 nm/RIU and 1210.0 nm/RIU, respectively, and the corresponding FOMs are 1295.4 and 762.3. Therefore, the high FOM of the composite grating based on SPR sensor possesses great potential applications in biochemical sensing.

VO2 based Mott transition field effect transistor is a new element to be incorporated between microbolometer sensitive pixels and on-chip read-out circuitry to fully realize the planar integrated infrared focal plane array. Based on their dielectric dispersions in Lorentz model, its infrared absorption was studied by the theory of reflection from Al surface plasma and absorption by optical phonons in VO2 and especially in α-SiN: H films. The present paper reports on the properties of the absorption in different wavelength regions and the dependence on the thickness of the nitride passivation layer, the absorbance spectra for the layer with thickness of λ/4n after the phase delay is corrected, and the changes in the spectra caused by the transition in the VO2 film.